Typewriting machine



P 1945- J. F. SMATHERS 2,385,035

TYPEWRITING MACHINE Filed March 18, 1941 2 Sheets-Sheet 1 ATTORNEY Sept.18, 1945. J, 'F. SMATHERS 2,335,035

TYPEWRITING MACHINE Filed March 18 1941 Sheets-Sheet 2 1 o LI.

f NVENTR BY Patented Sept. 18,1945

TYPEWRITING MACHINE James F. Smathers, Rochester, N. 'Y., assignor toInternational Business Machines Corporation, New York, N. Y., acorporation of New York Application March 18, 1941, Serial lilo.383,918-

16 Claims.

This invention relates to typewriting machines.

The ooject of the present invention is to provide an improvedproportional escapement mechanism, that is, an escapement mechanismwhich spaces the carriage of a typewriting machine in proportion to thewidths of the letters typed.

In the ordinary typewriting machine, a fixed space is allotted eachcharacter regardless of its width and narrow letters, like the l, arespaced exactly the same as letters which would ordinarily beexceptionally wide, such as the upper case The result. is that in orderto create an artistic impression and at the same time keep the letterswithin the confines oi. the space alotted to them, lower case letterslike i are often made wider than they should be and letters like theupper case W are made narrow. Consequently, typewriter type is usually acompromise.

It has been proposed to equip typewriters with type which is similar tothe type used by printers, designed for artisticness and maximumlegibility. However, such type, when used in a typewriting machine ofthe usual sort, appears inartistic and crude because the spacingbetweenthe letters of words is uneven in consequence of many of theletters being very narrow like the letter "1 while others are very wideand may even have a tendency to overlap.

The present invention is concerned with an improved mechanism which willcause the carriage of a typewriting machine to space variable extents tosuit the letters typed so that each letter fits in its allotted spacewithout overlapping and without unsightly gaps. e

Other objects of the invention will be pointed out in the followingdescription and claims and illustrated in the accompanying drawings,which disclose, by way of example,'the principle of the invention andthe best mode, which has been contemplated, of applying that principle.

In the drawings:

Fig. 1 is an elevation of the escapement mechanism as it would appearviewed from the front of a machine in which it is installed.

Fig. 2 is a large scale plan view of the escapement mechanism.

Fig. 3 is a vertical section on the line 3-3 in Fig. 2.

Fig. 4 shows the escapement dogs.

Fig. 5 is a vertical section on the line 5-5 in Fig. 2.

In the drawings, l0 designates a part of the framework of a typewritingmachine which is here shown as a vertical plate on the front face ofwhich is Journaled the spring motor II by' means of a stud I2. Securedto the spring motor II is a gear l3 which meshes with a rack it havingsuitable connections to the carriage of' the typewriting machine. Thespring ii of spring motor I I urges the gear l3 in a counterclockwisedirection (Fig. 1) and thereby tends to feed the rack l4 and thecarriage to the left. the letter spacing direction.

Pivoted on a stud it carried by the frame plate ID are three spacingdogs designated l1, l8, I9, each having a tooth Ha, I811, I911,respectively, engaging the teeth of a ratchet 20 secured to the springmotor i l. 'The spacing dog IT has a hole loosely receiving stud l8,and, with the parts in the position shown in the drawings, preventsrotation of the ratchet 20 under the influence of the spring l6 andthereby holds the carriage against movement in letter spacing direction.Also pivotally mounted on the stud I8 is a holding dog 2| having a toothengageable with the ratchet 20 and a lug Zia projecting.

under the spacing dog IS.

The spacing dogs i1, l8, l9 are held in spaced relation and guided byvertical slots in a bracket 22 secured to the plate In and are urged ina clockwise direction by means of springs 23 anchored to a pin 24carried by plate ill. The dog 2! is urged in a counterclockwisedirection by a spring 25 anchored to a pin 28 carried by plate l0.However. the spring 23 for the spacing dog I9 is stronger than spring 25for holding dog 2|, thereby enabling the dog 2i to follow the movementsof the dog is in a counterclockwise I direction. The dog 2 i may betermed the holding dog since its function is to temporarily hold theescapement wheel or ratchet 20 against rotation when one of the dogs l1,l8, or it is operated. The dog 2| does not control the amount of spacingbut merely prevents rotation of the ratchet 20 during the transitionperiod of th operation of the escapement.

The spacing dogs l1, l8. l9 determine the extent of spacing imparted tothe carriage and for this purpose are selectively controlled andoperated. The dogs I! and I9 are slotted at their pivots (Fig. 4)instead of being provided with a round hole, and the slot in the dog Itis'twice as long as the slot in the dog It. The ratchet wheel 20,, willnormally be held by one of the dogs l1, l8, and i9, but for presentpurposes it can be assumed that the dog I1 is holding the ratchet wheel.

Each time the carriage is to be spaced and the escapement mechanism isoperated for this purpose, all three of the dogs i1, i0, and it areratchet 20 to turn one tooth space.

disengaged from the ratchet wheel 20 and the dog 2| is caused to beengaged with the ratchet wheel. Assuming for the moment that all threespacing dogs l1, l8, ID are raised and lowered, the carriage is allowedto escape one tooth as in a simple escapement mechanism. It should bementioned that the dogs are so designed that the tooth on the dog 2|will move into a tooth space in the ratchet 20 before any of the teethl'la, I811, or |9a can become disengaged from the ratchet 20, thus whenthe dog I1 is free to drop, the ratchet 20 will be permitted to escapeonly one tooth with a complete operation of the escapement mechanism.

The slot in the dog I8 is of such length that an additional tooth spaceof movement is permitted when the I! is held up and only dogs i8 and I9permitted to reengage the ratchet 20. The dog i8 is normally held to theright by its spring 23 and, in consequence of the length of the slot,

when it reengages the ratchet 20, the superior tension of the spring l5will cause the dog l8 to slide on its pivot It to the left an additionaltooth space and will remain there until the escapement is operatedanother time. Similarly the dog i9 ratchet or escapement wheel 20, thelevers 30 operate a selector device which determines which of the dogsl1, l8, I8 is to be eifective to determine the spacing by controllingthe amount of rotation of the ratchet wheel 20. This mechanism is mostclearly shown in Figs. 3 and 5 and includes a slide 4| which is mountedon the bracket 36 for horizontal movement, it being attached to thebracket by means of screw studs 42 allows two additional spaces if italone is allowed to drop. Since the dog I! cannot slide on its pivot, itwill only allow the escapement wheel Thus the spacing dog H, inconjunction with the dog 2|, acts as an ordinary escapement. After eachoperation of the escapement mechanism one of the dogs i1, i8, i9 will beholding the ratchet 2D and, each time the escapement is operated, all ofthe spacing dogs i1, l8, l9 are disengaged from the ratchet and the dogsi8, i9 will be drawn to the controlled by the typewriter character keys.Ex-- tending underneath all of the spacing dogs 'li. l8, i9 is a commonoperating member 27 pivoted on a stud 21a carried by the plate Ill. Thisoperating member is in the form of a plate having ears at its endsprovided with holes through which the stud 21d passes and, when rockedin a counterclockwise direction, acts as a bail to lift all of the dogs01, I8, I9 out of engagement with the ratchet 20. i

For the purpose of operating the member 27, there are provided threelevers designated 28, 29, 30 which are pivoted on a stud 3| (Figs. 1 and2) carried by the plate It). These levers are urged in acounterclockwise direction by means of springs 32 anchored to a pin 33carried by the plate ill but movement in this direction is limited by astop pin 34 also carried by plate it. The levers 28, 29, 30 are spacedfrom each other on the stud 3! by means of suitable collars and are alsoguided by vertical slots in brackets 35, 36 attached to the plate 10.The levers 28, 29, 30 may be connected by links 31 to three bails as(Fig. 1) which may i be pivotally mounted on a rod 39, suitablysupported in the rame of the machine. These bails 'may underlie or beclosely associated with the which extend through horizontal slots in theslide 4|. The slide 4| is formed with a selector lug 4|a. which ispositioned differentially by moving the slide 4|, this being effected bythe levers 28, 29, and 30.

The lower edge of the slide 4| is provided with three notches or camslots designated 4|b, Me, and it. These notches are so shaped andarranged that the slide 4| will be cammed to right or left (Fig. 5)difierent extents according to which of the levers 28, 29, and 30 isoperated, unless the slide already stands in the position which is to bedetermined by the operation of a selected lever 28, 29, 30. In Fig: 5the slide ii is shown in the position it occupies after the lever 28 hasbeen operated to produce a single unit of spacing. It will be observedin Fig. 5 that if lever 28 is operated, it will not affect the slide llbut will actuate the member 21 to lift both of the dogs i1 and I8 out ofengagement with the ratchet wheel. Upon the release of the lever 28, thedogs 81 and i9 will be allowed to reengage the ratchet wheel 20, thistaking place before the dog 2| is fully released from the ratchet wheel.Since the dog i1 is incapable of sliding on its pivot, the ratchet wheelwill be permitted to rotate one tooth space to impart to the carriage asingle unit of spacing. The dog I 9, under these conditions, is merelyoperated idly and has no eflect. It will be noticed in Fig. 5 that thedog It is held by the lug 4 la out of engagement with ratchet 20.However. even if such dog did engage the ratchet, it. nevertheless,would have no effect as the dogs I! dominate in influence over the dogsl8 and i9.

Now let it be assumed that the lever 29 is operated with the parts inthe position of Fig. 5. The upward movement of the left hand end(Fig. 1) of the lever 29 cams the slide M to the right (Fig. 5) untilthe lever 29 enters the straight portion of the notch 4lc, therebypreventing further movement of the'slide 4|. lit will be understood thatbefore this happens, however, the lever 29 will lift the member 21 farenough to raise all of the dogs ll, l8, l9 before the slide 4| starts tomove to the right, to prevent the end of the do I! from blockingmovement of the slide M by contact with the side of lug die. Thus, theoperation of the lever 29 positions the lug illa underneath both of thedogs i1 and it and allows only the dog Is to reengage the ratchet wheel.The dog 2| allows the ratchet wheel to turn approximately half a toothspacewhen the do s ll, i8, i9 are raised in consequence of the clockwisemovement with reference to Fig. l. of lever 29. When the dog l9reengages the ratchet wheel, however, the dog 2| is disengaged and thespring of the spring drum causes the ratchet wheel to turn an extentwhich is limited by the long slot in the dogl9. This dog has its slotsso proportioned that an additional two and one half spaces of movementof the ratchet wheel is per mitted, whereby a total of three units ofspacing will be imparted to the carriage. The slide 4| will I remain inthis position until either the lever 28 or lever 30 is operated. Thus ifseveral charactors calling for three units of spacing are tyl dinsuccession, the cycle of operation will be repeated and will differonly that the dog I! will not be raised but will already be in raisedposition in consequence of the previous operation, and the dog I! alonewill be operated.

When the lever 80 is operated, it cam the slide ll to the right (Fig. asfar as it will go,thereby moving the lug 4 la under the dog I1 andpermitting both dogs l8, I! to reengage the ratchet wheel 20. Since thedog I8 has a shorter slot than the dog [9, the ratchet wheel will bepermitted to rotate one less tooth space when the dogs l8, l9 reengagethe ratchet wheel, whereby only two spaces of the carriage will takeplace. The notches lib, llc, and Md are so shaped that no matter whatthe position of the slide ll, any lever 28, 29, 30 except the last oneoperated is capable of moving the slide to a new position.

In Fig. 1 there has been shown somewhat diagrammatically one means ofselectively controlling or operating levers 28, 29, 30 according to thekey depressed. However, this specific disclosure is purely by way ofexample as it is contemplated that the mechanism be used in a poweroperated typewriter where the elements Ill may consist of levers or armswhich are operated by the individual type bar operating members ordevices instead of being directly actuated by or part of the keycharacter levers. For example, a modified selector mechanism operated bycam units such as is shown in Patent No. 2,224,766 may be used in whichthe links I 46 of the patent actuate the levers 28,19, 30 of Fig. l.

While there has been shown and described and pointed out the fundamentalnovel features of the invention as applied to a single embodiment, itwill be understood that various omissions and substitutions and changesin the form and details of the device illustrated and in its operationmay be made by those skilled in the art without departing from thespirit of the invention. It

- is the intention, therefore, to be limited only as indicated by thescope of the following claims.

What is claimed is:

1. In a machine having a carriage, the combination of a ratchet wheeldriven with the carriage, a holding dog engageable with the ratchetwheel; a series of spacing dogs engageable with the ratchet wheel, aplurality of which spacing dogs are mounted for different restrictedmovements to permit the ratchet wheel to rotate a plurality of differentextents according to which of the spacing dogs is selectively renderedeffective, at least one of said spacing dogs normally engaging theratchet to prevent rotation thereof;. operating means for engaging theholding dog with the ratchet and disengaging all of the spacing dogsfrom the ratchet to permit rotation thereof, and a selector elementselectively set by the operating means to any one of a plurality ofpositions to selectively control reengagement of the spacing dogs withsaid ratchet wheel.

-2. In a carriagespacing mechanism for a typewriting machine, a ratchetwheel rotatable to control theextent of letter spacing of the carriage,a plurality of spacing dogs engageable with the ratchet wheel andmovable different extents tangentially of said wheel to control rotationthereof different extents according to which of said dogs is engagedwith the ratchet wheel, operating meansfor disengaging the spacing dogsfrom the ratchet wheel, and a. selector device operated by the lastnamed means for selectively controlling the reengagement of the spacingdogs with the ratchet wheel.

3. In combination with the carriage or a typedifferent extents forcontrolling different extents of movement of the first named element, aholding element operable when thespacing elements are renderedineffective to hold the first element, means for rendering the spacingelements ineffective and the'holding element effective, and selectingmeans operated by the last named means for selectively renderingeffective the spacing elements.

4. In combination with the carriage of a typewriting machine, arotatable element driven with the carriage, a plurality of spacingcontrol elements, at least one of which is normally engaged with therotatable element'to prevent rotation thereof, said control elementsbeing movable different extents to limit rotation of the rotatingelement and disengageable from the rotating element; a holding elementengageable with the rotatable element when the spacing control elementsare disengaged therefrom to prevent rotation of the rotatable element,means common to the spacing control elements for disengaging saidcontrol elements from the rotatable element, and a selector devicesettable with each operation of the spacing control elements toselectively control the reengagement of the spacing control elementswith the rotatable element.

5. In combination with the carriage of a typewriting machine, a ratchetwheel movable with the carriage, a plurality of spacing dogs.selectively engageable with the ratchet wheel and member movabletransversely of the spacing dogs to selectively prevent the spacing dogsfrom reengaging the ratchet wheel, and a series of levers for actuatingthe common operating means and selectively moving the transverselymovable member.

6. In combination with the carriage of a typewriting machine, toothedmeans -movable with the carriage, a plurality of spacing dogs engageablewith the toothed means and movable different extents by the ratchetwheel, a holding dog normally disengaged from the toothed means andmovable into engagement therewith to hold the toothed means temporarily,means to disengage all of the spacing dogs and at the same time causethe engagement of the holding dog with the toothed means, and selectingmeans to control the reengagement of the spacing dogs with the toothedmeans.

7. In a carriage spacing mechanism, an element movable to control theextent of feed of the carriage, a series of spacing members selectivelypivotally engageable with and disengageable from the movable element,certain of said members being slidably movable different extentstransversely of their pivots 'by the movable element when engaged withsaid element to control movement thereof and selecting means forcontrolling the number of said spacing members engaging said element,and operating means for alternately engaging and disengaging saidmembers.

8. In a carriage spacing mechanism, a ratchet wheel rotatable to controlthe extent of feed of the carriage, a plurality of pivoted spacing dogsengageable with the ratchet wheel and movableon their pivots differentlimited extents to control rotation of the ratchet wheel; and means toselectively engage the spacing dogs with the ratchet wheel, including adog selecting element and a series of levers each for moving theselector element to a different extent from the others.

9. In a carriage spacing mechanism, a toothed member moved with thecarriage; a, plurality of spacing dogs, each defining a difierentspacing of the carriage and movable difi'erent extents in parallelplanes, said spacing dogs also being movable in said planes intoengagement with said toothed member; a selector element movabletransversely of the spacing dogs to selectively control their engagementwith said toothed member, operating means for controlling engagement anddisengagement of said spacing dogs with said member and for selectivelymoving said element, and a holding dog movable into engagement with saidtoothed member when said spacing dogs are wheel driven with thecarriage; a plurality of pivoted spacing dogs engageable with theratchet wheel, at'least two of said spacing dogsubei ng slidably movableon their pivots different extents variably to limit rotation of theratchetwheel; means to operate the spacing dogs, including means todisengage said dogs from the ratchet wheel and means to selectivelyengage the spacing dogs with the ratchet wheel by a pivotal movement ofsaid spacing dogs; and means for holding the ratchet wheel againstrotation when the spacing dogs are disengaged from the ratchet wheel.

11. In a carriage spacing mechanism, a plurality of spacing dogs for thecarriage; a toothed member connected to'the carriag for controlling theextent of feed of the carriage, the teeth on said member having widefacesto be enga'geable by any one of said spacing dogs independently ofthe others, each spacing dog having a path of movement different inextent from the others to cause a difierent degree of movement of thetoothed member, means to engage and disengage said dogs, and a selectingdevice for controlling the engagement of the spacing dogs with saidtoothed member.

12. In a carriage spacing mechanism, a toothed member movable with thecarriage, a series of spacing dogs movable different extents to causedifferent extents of feed of thetoothed member, at least one of whichspacing dogs is normally in engagement with said toothed member, saidspacing dogs being movable away from said toothed member, a holding dogcommon to the spacing dogs and movable into engagement with thetoothedmember when the spacing dogs are released therefrom; an elementselectively movable transversely of said spacing dogs for selectivelypreventing reengagement of the dogs with the toothed member, said lastnamed member being arranged to permit different ones of said spacingdogs to reengage the tooth member according to the position of saidmember, means to disengage said dogs from said member, and keycontrolled means for selectively moving said element.

13. In a carriage spacing mechanism, a ratchet wheel rotatable tocontrol the extent of feed of the carriage, a plurality of pivotedspacing dogs engageable with the ratchet wheel and movable in adirection transversely of their pivots diflerent extents to control therotation of the ratchet wheel; and means to selectively engage thespacing dogs with the ratchet wheel including an element having a seriesof cam surfaces and movable to a plurality of different positions toselectively prevent the dogs from engaging the ratchet wheel, each camsuri'ace corresponding to a different position of said element, a seriesof selectively operable levers cooperating with the cam surfaces in themovable element for moving said element to its different positions, andmeans for engaging said dogs with said ratchet wheel and disengagingsaid dogs from said ratchet with each operation of one of said levers.

14. In a carriage spacing mechanism, a toothed member moved with thecarriage; spacing dogs, each movable a different extent from the othersto effect different extents of spacing of said toothed member andseparately independently movable into and out of engagement with saidtoothed member; a member common to all of said dogs for moving themoutof engagement with said toothed member, a holding dog common to saidspacing dogs and movable into engagement with said toothed member whenthe spacing dogs are disengaged, and means for selectively controllingengagement of said dogs with said toothed member.

15. In a carriage spacing mechanism, a member moved with the carriage, aplurality of space defining members cooperating with said carriage movedmember and releasable therefrom, each of said space defining membersbeing movable different extents from the other to effect difierent feedsof the first member; means to release all of said members as a group,detent means for the carriage moved member rendered operative when thespace defining members are released, and means to selectively retaincertain of said elements in a released condition upon each operation ofthe operating means. 16. In a carriage feed mechanism, toothed meansmovable to control the extent of feed of the carriage, a plurality offeed controlling elements operatively engageable with the toothed meansand having different limited extents of movement and selectable to varythe extent of movement of the carriage by the toothed means, actuatingmeans for said elements for effecting first their disengagement fromsaid toothed means and then tending to reengage said elements with thetoothed means; and selecting means for controlling the engagement of thefeed controlling element with said toothed means, said selecting meansincluding a member movable variable extents to selectively control thereengagement of the feed controlling elements with said toothed means,said member enabling a selected one of the feed controlling elements tooperatively engage the toothed means upon each operation of theactuating means.

JAMES F'. SMATHERS.

